App of the day: Atlantis: Pearls of the Deep review (iPhone)

A classic match-'em-up game is always a good way to wile away the hours. Unlike the more traditional and rigid games of the genre where blocks fall into fixed positions, the Atlantis take is somewhat looser: with alleged real physics, coloured pearls bounce and roll which can make matching them up that much tougher.

Atlantis: Pearls of the Deep

Your job is to drop said coloured pearls into play and match up groups of three. It's possible to match four or more, or fire off combos with multiple matches from a single move.

There are three goals in each level, each of which will earn you a star and, in turn, a coin.

The first is a set number of sea shells placed within certain pearls set around each level - match them with correlating colours and that's goal one down, one coin in the bag. Of course these desirable pearls might be surrounded by a mixture of different coloured pearls in order to make play that much more difficult.

Time-based and maximum pearl limits per level equate to the other two goals in the majority of levels. You'll need to be fast and half-skilled to work though a level to achieve maximum return. It's possible to switch the current pearl with the next pearl in line by tapping to the top of the screen and this can be useful for tactical play.

You'll be needing those coins as they are, at least in numerous numbers, the key to unlocking future episodes and more levels. It's 50 coins for the second set, 150 for the third and the same for each episode thereafter.

But hang on, with only 15 levels per episode it doesn't take a genius to work out that each episode requires more than just maxing out each level. The developers' intents here are obvious: buy in-game coins with real-world cash to access additional episodes quickly. That's one way of doing it - some, we're sure, will pay, while others (us included) will be more inclined to put the game down or just uninstall it.

We don't mind paying for quality apps, and Atlantis: Pearls Of The Deep does fall into that category. But we'd have probably been happier to just fork out 99p for it in the first instance and have full access to all episodes and levels.

However, a more recent update to the game has added a "Zen" section where it's possible to earn a coin per level up to 10 levels a day. Okay, so it will take 15 days to acquire the 150 coins to unlock these later episodes sets, but the Zen games - which have the sole goal of clearing the screen - are fun to play, and there is replay value in the earlier levels too.

That's part of the point really: this is a game, and a fun one at that. Dipping in to listen to the mellow tunes while bouncing pearls around the screen is fun escapism.

Later levels get trickier as they add locked-down, weed-ridden pearls, various rotational platforms, wheels and even ramps where you'll need to launch your coloured pearls precisely for best results. Special power-ups can also be bought, but they tend to take your eyes off the prize which, ultimately, is to earn enough coins to progress.

It all keeps the interest levels up in a game that could otherwise become very repetitive. But even when it does feel as though you're done, there's that call from the deep that sucks you back in to play some more. Atlantis: Pearls of the Deep may not be perfect, but there's a lot of value in giving it a whirl.